$\begin{aligned}&\phantom{{\times}}2\\ \\ &\underline{\times4}\\ \\ \end{aligned}$ $~~$
Solution: We can think of ${2} \times {4}$ as $2$ rows of $4$ circles. How many circles are there? ${1}$ ${2}$ ${3}$ ${4}$ ${2}$ ${\color{#AA87FF}{1}}$ ${\color{#AA87FF}{2}}$ ${\color{#AA87FF}{3}}$ ${\color{#AA87FF}{4}}$ ${1}$ ${\color{#AA87FF}{5}}$ ${\color{#AA87FF}{6}}$ ${\color{#AA87FF}{7}}$ ${\color{#AA87FF}{8}}$ $\begin{aligned}&\phantom{{\times}}2\\ \\ &\underline{\times4}\\ \\ &\phantom{{\times}}C8 \end{aligned}$